Amount of tribute must absolutely be defined before degummed and bleached oil is fed to deodorization unit. Determination of the definite amount of tribute can be done by weighing in a feeding tank on loading cells or by the volume of the degassing tank on deodorization.
The start signal at the automatic controlled process of the plant is the pumping in of the raw oil. Every independent oil tribute is introduced to deodorization step by step following the steps as follows: degassing, heating with heat exchanger of heater, final heating with high pressure steam, deodorization, cooling with the heat exchanger of heater and cooling with indirect cooling liquid.
The advantage of PLC controlled process is that it makes possible change of feeding oil of different type without interrupting the normal deodorization operation, with the possible lowest product mixture ratio.
General edible oils and tallow are deodorized in temperatures varying between 230-260°C and about 3 mbar pressure.
Continuous deodorization and de-acidification process principle with scraper column
The degummed and bleached oil is first pre-heated via heat transfer in the heating system made of hot deodorized oil. Then it is brought to final process temperature by indirect high pressure steam heating.
For the de-acidification of higher free fat acids, remaining time in scraper column at higher scraper temperatures is with lower temperature (heat change in the middle is optional).